In the upper region of -River Kanda found in the eastern part of the Musashino Upland which is overlaid with the Kwanto Volcanic Ash, the ground water-table slants toward the valley on both sides. (cf. Fig. 1) The discharge of this river in this area increases, though very gradually, as the river flows down. From these facts, we presume River Kanda is being nourished by the ground water.
At present, the slopes of the precipices forming the valley are different on both sides-the form of the valley is assymmetrical. Where the slope of the precipice is steeper on the north side than on the south, the ground water- table slants toward the north. Where the slope is, steeper on the south side than on the north, the ground-water-table slants toward the south. (cf. Fig. 6) Gathering up these facts, the author believes that the assymmetrical valley wall is related to the declivity of the water table.
The ground heaves up gradually in the vicinity of the valley. This seems to be due to the dampness of the ground and to the abundance of the vegetation in the valley region; that is, the darn press of the ground and vegetation protect the ground from the strong Musasllino winds seen elsewhere which blow away the dried mud and causes wind-erosions. If the valley were to be filled up, we would, obtain a convex ground feature.
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